A Phase 2b, Double-Blind, Randomized Extension Study to Evaluate the Long-Term Safety and Efficacy of PTC518 in Participants With Huntington’s Disease

Phase 1

Recruiting

Conditions: Huntington's Disease
MedDRA version: 20.0Level: PTClassification code: 10070668Term: Huntington's disease Class: 100000004850
Therapeutic area: Diseases [C] - Congenital, Hereditary, and Neonatal Diseases and Abnormalities [C16]

Registration Number: CTIS2023-504628-24-00

Lead Sponsor: PTC Therapeutics Inc.

Brief Summary: Not available

Detailed Description: Not available

Recruitment & Eligibility

Status: Recruiting

Sex: All

Target Recruitment: 358

Inclusion Criteria

Ambulatory male or female participant aged 25 years and older, inclusive, who has completed the Treatment Period in Study PTC518-CNS-002-HD, Participant is willing and able to provide informed consent and comply with all protocol requirements, Women of childbearing potential (WOCBP) must agree to use highly effective methods of contraception during dosing and for 6 months after stopping the study medication., Sexually active and fertile males must use a condom during intercourse while taking study drug and for 6 months after stopping study drug and should neither father a child nor donate sperm in this period. A condom is required to be used also by vasectomized men in order to prevent potential delivery of the drug via seminal fluid.

Exclusion Criteria

Individuals are not eligible to participate in this study if they have not previously completed the Treatment Period in Study PTC518-CNS-002-HD.

Study & Design

Study Type: Interventional clinical trial of medicinal product

Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Main Objective: Safety - Evaluate the long-term safety of PTC518 in participants with Huntington’s disease (HD)<br>Efficacy - Evaluate the pharmacodynamic effects of PTC518 through the reduction in blood total huntingtin (tHTT) levels;Secondary Objective: Assess the long-term effects of PTC518 on change in caudate volume by volumetric magnetic resonance imaging (vMRI) Assess the long-term effect of PTC518 on change in composite Unified Huntington’s Disease Rating Scale (cUHDRS), Determine the long-term effect of PTC518 on mutant Huntingtin (mHTT) protein levels in cerebrospinal fluid (CSF) and blood;Primary end point(s): Safety profile as characterized by TEAEs, laboratory abnormalities, vital signs, physical examination, C-SSRS, Evaluate blood tHTT protein levels over time

Secondary Outcome Measures

Name	Time	Method
Secondary end point(s):Change in caudate volume as assessed by vMRI over time;Secondary end point(s):Change in cUHDRS scores over time;Secondary end point(s):Evaluate CSF mHTT protein levels over time;Secondary end point(s):Evaluate blood mHTT protein levels over time